peterh Posted September 23, 2016 Report Share Posted September 23, 2016 Hasn't been much activity here so thought I would offer some things I have recently done to my 2015 JGas JT250: Fitted an OKO 26mm carb – model K103BT - http://oko-australia.com.au/trials in replace of the standard Dellorto PHBL26. Stayed with the 26mm OKO rather than a 28mm due to the type of riding I do (i.e. no splat walls) and apparently easier to tune, jetting and air-screw wise. To fit the OKO, I used the JGAS accessory intake manifold part for Keihin PWK carby’s to accommodate the larger diameter needed. Fitted a 5mm intake manifold spacer – http://trialparts-shop.de/en/shop/jotagas/vergaserflansch-jotagas/ which accommodates the slightly shorter length of the OKO compared with the Dellorto Fitted Dual Stage Boyesen PowerReeds (model # 6TR123) Removed the angled cable guide from the Dellorto and used it in the OKO – uses the same thread (used some threadseal for peace of mind) as this allowed my original cable to be used. Set up the OKO with needle in the middle position (3 from top or bottom) and fitted a 48 pilot (standard issue was 45) and kept the main at 115 Air screw is 1 to 1¼ turns out. I use an NGK BPMR6Y plug – a v-grooved electrode plug. Standard recommendation is the NGK BPMR6A I use Maxima 927 at 80:1 – love the smell and also having used a usb micro camera into the bore, the top of the piston is lovely and clean and very light tan shiny colour. This is different than what I had seen before with my previous Jotagas on a different synthetic oil. My impressions are: Carburation is improved compared with the setting up of the Dellorto that I had done previously. There is smooth transition throughout the range from idle to WOT. There is no hesitation (fluffiness) in transition from ¼ throttle to mid-range as there had been, despite my attempts to tweak this in the Dellorto. Improved low end torque – I am using 2nd gear now much more commonly and being able to pull off the bottom at low idle without hesitation (albeit hopefully with my good throttle control). The improved low end torque is characteristic of Boyesen Reeds from my experience in other bikes and to me has made the JGas even better in that area that it is already. I could tweak the set up a little further but prefer a slightly richer setting than being too lean, particularly for transitions between sections. And currently the bike pulls easily and consistently throughout the range of throttle response. As in a previous post with my 2014 Jotagas 250, I have also “dremelled” the frame to increase turning circle (3.5mm into the frame on each side) and that greatly improves turning – saves me having to think about perfecting hopping to turn. I recently had my Elka shock serviced and apparently some re-valving that seems to have reduced bottoming out. If you are interested in spending time in the shed in tweaking your bike – just because you can – then give the above some thought. I am very happy with the outcome – and yes, of course I have to say it has helped my riding (got to justify it), giving confidence particularly in those low speed, 1st or 2nd gear tight turn climbs and double-blips and letting the bike just work smoothly from low down right through the range. 2 Quote Link to comment Share on other sites More sharing options...
collyolly Posted September 23, 2016 Report Share Posted September 23, 2016 Is it the quality of the picture or is your rear tyre past its best ? Here in South East England good grip from the tyre is the first priority. Quote Link to comment Share on other sites More sharing options...
lineaway Posted September 23, 2016 Report Share Posted September 23, 2016 From the dry rocks we ride, that tire is good for another year or more! 2 Quote Link to comment Share on other sites More sharing options...
peterh Posted September 23, 2016 Author Report Share Posted September 23, 2016 Yes, tyre was beyond it's best, battered about on limestone ledges, steps, sand and dry conditions here in Western Australia. Not much mud, mud and slippery, slimy tree roots. Quote Link to comment Share on other sites More sharing options...
guys Posted September 23, 2016 Report Share Posted September 23, 2016 Good on ya mate, but your work isn't finished yet though. Still have to cut a piece off of that hose clamp on the carbie. But no worries mate, I'm just nitpicking. Quote Link to comment Share on other sites More sharing options...
cascao Posted September 23, 2016 Report Share Posted September 23, 2016 My bike was this clean only in it first day Quote Link to comment Share on other sites More sharing options...
peterh Posted September 24, 2016 Author Report Share Posted September 24, 2016 My bike was this clean only in it first day A clean in trials is better than a messy 3 or worse, a 5 Quote Link to comment Share on other sites More sharing options...
slik Posted September 24, 2016 Report Share Posted September 24, 2016 Nice job ! Could you post a picture of all the bike ? Quote Link to comment Share on other sites More sharing options...
peterh Posted September 26, 2016 Author Report Share Posted September 26, 2016 Pics as requested. Taken today before off to a practice session up at our Club's Trial Park. Rocks, rocks and more rocks. Bike has about 100hrs on it. A few other tweaks was to replace the standard bash plate with the thicker version that also extends further back - replaced the standard countersunk bolts with longer countersunk ones and put a nyloc nut on the ends - keeps things much more secure. Also replaced the standard oil breather with an accessory part that breathes through the filler - obtained from the same place as the intake spacer on the carby manifold. 1 Quote Link to comment Share on other sites More sharing options...
slik Posted September 26, 2016 Report Share Posted September 26, 2016 Thank you Peterh , nice bike , be nice till 200 hours ! Quote Link to comment Share on other sites More sharing options...
fabio_br Posted October 26, 2016 Report Share Posted October 26, 2016 Hi, Peterh, Where did you find this fuel tank cap? And the curve protector (carbon)? Quote Link to comment Share on other sites More sharing options...
peterh Posted October 27, 2016 Author Report Share Posted October 27, 2016 Hi Fabio, The fuel tank cap was from here: http://trialparts-shop.de/en/produktkategorie/jotagas/ - same place as the oil filler breather and the flange for the carburettor. The carbon-look (not real carbon fibre) are Jitsie frame protectors. I also have fork protectors and the exhaust protector. I got these from The Hellteam here in Australia - http://www.thehellteam.com/products/protectors/frame.html but should be available from Jitsie stockists. Quote Link to comment Share on other sites More sharing options...
ilovetrials Posted October 30, 2016 Report Share Posted October 30, 2016 (edited) Trialparts DE web page is not working..!! Edited October 30, 2016 by ilovetrials Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.